Question

Let’s say an user click on a button. The client receive some data that I use latter. If user receive number 2, next time when click again I need to know was 2. The user don’t see this number.

I use hidden input for latter use
or
cookies/sessions
or
other things?

Answer 1

Sessions will work:

session_start();
$_SESSION['number'] = 2;

• Cookie values are available to the user because they’re stored on the client’s computer.
• Hidden fields can be viewed via the source.
• Session values are stored on the server (or in a database). The only thing should be available to the client is the session ID, which is usually stored in a cookie.